If you're talking about a power amp with a speaker cab the VS workhorses might do the trick. I don't really know how they would sound when driven like a proper tube power amp section should though.
wan, u can get the carvin ts100 tube poweramp..
its retails at 499US but u can order it at Ranking Sports.
anyway wat preamp are u using right now??
if u have sufficient fund i recommend get a small cabs as well..rather than
connecting via effects loop ...
u dun need a poweramp to connect to the effects loop..